Traian Rebedea | University Politehnica of Bucharest (original) (raw)

Papers by Traian Rebedea

Cet article présente un environnement-tuteur d'apprentissage pouvant s'insérer dans une plate-for... more Cet article présente un environnement-tuteur d'apprentissage pouvant s'insérer dans une plate-forme de FOAD permettant à des étudiants de prendre connaissance et de réviser des contenus de cours. Cet environnement puise son originalité dans le fait qu'il allie une approche cognitive et des références à l'apprentissage dialogique pour permettre : -de fournir aux apprenants les cours les plus pertinents à étudier étant donné leur compréhension du cours ; -de délivrer des feedback sur la compréhension d'un cours et le contenu de résumés produits sur ce même cours ; -de renvoyer des feedback sur les fils de discussions menées dans des chats.

Studying virtual math teams, 2009

This chapter introduces a theoretical framework for analyzing collaborative problem solving in ch... more This chapter introduces a theoretical framework for analyzing collaborative problem solving in chats, based on the concept of polyphony and Bakhtin's theory of dialog. Polyphony, a notion taken from music theory, may be considered as a general model for interaction and creativity by a group of people ("voices," in an extended sense) following patterns of counterpoint. As Bakhtin emphasized, polyphony may occur in texts; we will show that it can occur in problem-solving chat texts. One of the features of polyphonic music is its potential development of complex architectures starting from a given theme. Polyphonic structuring of dialogs may transform the interaction into a "thinking device": Different voices jointly construct a melody (story or solution), sometimes adopting different positions and then generating, identifying or solving dissonances (unsound, rickety stories or solutions). Polyphony consists of several "horizontal," longitudinal melody lines that are "vertically," transversally integrated. Similarly, in chats, the continuations of utterances are tied together over time providing a melodic line. Simultaneously, they are coordinated with the utterances of others, maintaining the integration toward unity across various themes and variations that sometimes can introduce differences. This chapter also proposes software tools for the visualization of the polyphonic weaving in chats. These tools identify and visualize the explicit and implicit links among utterances, and may determine or visualize the contributions of each participant in a chat.

Blended …, 2007

In this paper is presented a novel dialogistic, socio-cultural perspective and an associated soft... more In this paper is presented a novel dialogistic, socio-cultural perspective and an associated software tool, which provide structured visualisation and analysis means of Computer Supported Collaborative Learning chat conversations. The implemented tools use knowledge-based techniques and are based on Bakhtin's dialogistic paradigm. They visualize the threading of topics and utterances in the conversation and the contributions of the participants in collaborative learning during instant messenger chats. Natural language processing based on the WordNet lexical ontology and semantic distances are used for detecting topics in the chat and their threading. The experiments with the developed application were performed with students at a course on Human-Computer Interaction in Bucharest Politehnica University.

Computational Linguistics and Intelligent …, 2010

Discourse in instant messenger conversations (chats) with multiple participants is often composed... more Discourse in instant messenger conversations (chats) with multiple participants is often composed of several intertwining threads. Some chat environments for Computer-Supported Collaborative Learning (CSCL) support and encourage the existence of parallel threads by providing explicit referencing facilities. The paper proposes a discourse model for such chats, based on Mikhail Bakhtin’s dialogic theory. It considers that multiple voices (which do not limit to the participants) inter-animate, sometimes in a polyphonic, counterpointal way. An implemented system is also presented, which analyzes such chat logs for detecting additional, implicit links among utterances and threads and, more important for CSCL, for detecting the involvement (inter-animation) of the participants in problem solving. The system begins with a NLP pipe and concludes with inter-animation identification in order to generate feedback and to propose grades for the learners.

Times of Convergence. …, 2008

Online collaboration among communities of practice using text-based tools, such as instant messag... more Online collaboration among communities of practice using text-based tools, such as instant messaging, forums and web logs (blogs), has become very popular in the last years, but it is difficult to automatically analyze all their content due to the problems of natural language understanding software. However, useful socio-semantic data can be retrieved from a chat conversation using ontology-based text mining techniques. In this paper, a novel approach for detecting several kinds of semantic data from a chat conversation is presented. This method uses a combination of a dialogistic, socio-cultural perspective and of classical knowledge-based text processing methods. Lexical and domain ontologies are used. A tool has been developed for the discovery of the most important topics and of the contribution of each participant in the conversation. The system also discovers new, implicit references among the utterances of the chat in order to offer a multi-voiced representation of the conversation. The application offers a panel for visualizing the threading of the subjects in the chat and the contributions function. The system was experimented on chat sessions of small groups of students participating in courses on Human-Computer Interaction and Natural Language Processing in ”Politehnica” University of Bucharest, Romania.

… of the 9th international conference on …, 2009

Although instant messaging is a very popular tool for collaboration and it has been used for a wi... more Although instant messaging is a very popular tool for collaboration and it has been used for a wide variety of CSCL tasks, there are only a few applications for assisting the tutors in evaluating the conversations of the students. Due to the difficulty of this task, chat is seldom used in a formal education context. In order to tackle this problem, several applications were developed which assist the tutors when evaluating chat conversations. This paper presents a comparison of the evaluation results when using these applications on a set of three multi-user chat sessions.

Advances in Web Based …, 2009

The paper describes a complex e-learning experiment that has involved over 700 students that atte... more The paper describes a complex e-learning experiment that has involved over 700 students that attended the Human-Computer Interaction course at the “Politehnica” University of Bucharest during the last 4 years. The experiment consisted in using social web technologies like blogs and chat conferences to engage students in collaborative learning. The paper presents the learning scenario, the problems encountered and the tools developed for solving these problems and assisting tutors in evaluating the activity of the students. The results of the experiment and of using the blog and chat analysis tools are also covered. Moreover, we show the benefits of using such a scenario for the learning community formed by the students that attended this course in order to supplement the classical teaching and learning paradigm.

Foundations of Intelligent Systems, 2008

The paper presents an autonomous text classification module for a news web portal for the Romania... more The paper presents an autonomous text classification module for a news web portal for the Romanian language. Statistical natural language processing techniques are combined in order to achieve a completely autonomous functionality of the portal. The news items are automatically collected from a large number of news sources using web syndication. Afterward, machine-learning techniques are used for achieving an automatic classification of the news stream. Firstly, the items are clustered using an agglomerative algorithm and the resulting groups correspond to the main news topics. Thus, more information about each of the main topics is acquired from various news sources. Secondly, text classification algorithms are applied to automatically label each cluster of news items in a predetermined number of classes. More than a thousand news items were employed for both the training and the evaluation of the classifiers. The paper presents a complete comparison of the results obtained for each method.

Sustaining TEL: From …, 2010

Although Computer-Supported Collaborative Learning (CSCL) advocates the use of instant messaging ... more Although Computer-Supported Collaborative Learning (CSCL) advocates the use of instant messaging and discussion forums for collaboration between learners, there is a scarcity of tools for leveraging the information in this kind of conversations. Thus, these technologies are primarily used for communication and, once the conversation is over, the raw data is rarely manually analyzed by tutors, teachers and other learners. This paper presents a methodology and a system that can be used for providing feedback and support to learners and tutors that are involved in tasks that make use of chats and forums. In order to achieve this objective, PolyCAFe employs Natural Language Processing and Social Network Analysis techniques to discover polyphony and inter-animation in textual collaborations. To evaluate the proposed approach and the designed system a first validation experiment has been performed and the results are discussed and analyzed in the end of the paper.

In this paper we present a text recovery method based on a probabilistic post-recognition process... more In this paper we present a text recovery method based on a probabilistic post-recognition processing of the output of an Optical Character Recognition system. The proposed method is trying to fill in the gaps of missing text resulted from the recognition process of degraded documents. For this task, a corpus of up to 5grams provided by Google is used. Several heuristics for using this corpus for the fulfilment of this task are described after presenting the general problem and alternative solutions. These heuristics have been validated using a set of experiments that are also discussed together with the results that have been obtained.

Guest …, 2010

The aim of the workshop was to study theories, models and analysis techniques that enable us to u... more The aim of the workshop was to study theories, models and analysis techniques that enable us to understand the quality of collaborative activity in task-oriented computer-mediated interactions. In this context, the term ‗quality' can be understood in descriptive terms (identifying and discriminating the intrinsic properties of collaboration) and/or in a normative sense (identifying what makes ‗good' or less good collaboration, considered sui generis). These visions of quality can be complementary; and exploring this would require elaborating deep models of the processes of collaboration, articulated with assessment of the degree of achievement of collaboration goals in specific situations, and understanding of productive and creative potentialities of dialogue. Research originating across a broad variety of disciplines in social, cognitive and computational sciences can contribute to these theoretical and methodological aims, within a perspective of making constructive interventions in concrete collaborative work situations. Application domains range from various workplace situations (companies, hospitals, training institutes, schools, …) with varied tasks (collaborative design, learning, decision-making, …). Methodological approaches include qualitativequantitative interaction and group-work analysis, trace-log analysis, interviews, computational modelling, participant observation, workplace studies of technological mediation and transfer, usability studies, … Across these various fields there are several reasons why the study of quality of collaboration is important:

… (RoEduNet), 2010 9th, 2010

Abstract Depending on the user&amp;amp;amp;amp;amp;#x27;s intention, the queries processe... more Abstract Depending on the user&amp;amp;amp;amp;amp;#x27;s intention, the queries processed by a search engine can be classified in transactional, informational and navigational [1]. In order to meet the three types of searches, at this moment search engines basically use algorithmic analysis of the links between pages improved by a factor that depends on the number of occurrences of the keywords in the query and the order of these words on each web page returned as a result. For transactional and informational queries, the relevance of the results returned by the ...

This paper presents a method for the automatic detection and correction of malapropism errors fou... more This paper presents a method for the automatic detection and correction of malapropism errors found in documents using the WordNet lexical database, a search engine (Google) and a paronyms dictionary. The malapropisms detection is based on the evaluation of the cohesion of the local context using the search engine, while the correction is done using the whole text cohesion evaluated in terms of lexical chains built using the linguistic ontology. The correction candidates, which are taken from the paronyms dictionary, are evaluated versus the local and the whole text cohesion in order to find the best candidate that is chosen for replacement. The testing methods of the application are presented, along with the obtained results.

Natural Language Processing …, 2010

In supporting Lifelong Learning (LLL) on the Social Web (Web2.0), Natural Language Technologies (... more In supporting Lifelong Learning (LLL) on the Social Web (Web2.0), Natural Language Technologies (LT) increasingly play a central role due to the fact that text is the leading medium of communication and collaboration. LT cover now a wide range of topics, including advanced semantic resources and applications like ontologies, knowledge extraction, text mining, Natural Language Processing (NLP) and Latent Semantic Analysis (LSA). The peculiarities of Web2.0 impose also the consideration of using LT for social software (social networks analysis) and collaborative interactions on chats and forums. Pragmatics, discourse and conversation analysis are very important analysis domains.

This paper presents a model and an application that can be used to assess chat conversations acco... more This paper presents a model and an application that can be used to assess chat conversations according to their content, which is related to a number of imposed topics, and to the personal involvement of the participants. The main theoretical ideas that stand behind this application are Bakhtin’s polyphony theory and Tannen’s ideas related to the use of repetitions. The results of the application are validated against the gold standard provided by two teachers from the Human-Computer Interaction evaluating the same chats and after that the verification is done using another teacher from the same domain. During the verification we also show that the model used for chat evaluation is dependent on the number of participants to that chat.

Towards Ubiquitous …, 2011

The wider acceptance and usage of instant messaging (chat) represents one of the consequences of ... more The wider acceptance and usage of instant messaging (chat) represents one of the consequences of undertaking Computer-Supported Collaborative Learning (CSCL) practices in formal education settings. However, the difficulty of analyzing these textual artifacts of learners in order to offer them feedback represents a serious problem in further extending the usage of chat conversations. PolyCAFe is a system that was designed to support the tutors and to provide automatic feedback for the learners engaged in collaborative chat conversations and discussion forums. The architecture of the system is presented by focusing on two key components: the assessment of the utterances and of the collaborative discourse. PolyCAFe"s effectiveness has been proved in a validation experiment with students and tutors from a University course. The main findings from this trial, together with the conclusions of domain experts verifying the accuracy of the assessment provided by PolyCAFe, are also analyzed and commented in detail.